Electric-current interrupter.



No. 677,498. Patented July 2, l90l.

. E. w. CALDWELL.

I ELECTRIC CURRENT INTERRUPTER.

(Application fllsd m 4, 1899.)

' (No Model.)

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- UNITED STATES PATENT OFFICE.

EUGENEIV. CALDWELL, OF YORK, N. Y.

ELECTRIC-CURRENT lN'l'ERRUPTER SPEGIFI'CATION'forming part of Letters Eatent' No. 677,498, dated July2, 1901.

' Application filed May 4, 1899. Serial No. 715,557. (No model.)

Toall whom, it may concern: Be it known that I, EUGENE \V.CALDWELL,- aciti'zen of the UnitedStates, and a resident. of the city of New York,.in the borough of 5 Manhattan, county of vNew York, and State of New York, have invented acertain new and useful Improvement in Apparatus for Interrupting Electric Currents, of which the -fol-.

lowing is a specification, reference being had to the drawings accompanying and forming a part of the same.

The present invention relates to a new apparatus for interrupting, especially at high rate of frequency, an electric current or .cir-' cuit. I

The invention as herein illustrated and described is applicable to an interrupter for use in connection with an induction-coil, es-' pecially such a coil as is used for X-ray work;

- but it is to be understood that this interrupter may be used with other apparatus requiring an electric-current interrupter.

In descriptive terms the invention consists 'of an electricconductor, a portion or section "of which is composed of a fluid, a-partof which is so confined that as the current passes it will beevaporated or rendered gaseous, and thereby the. circuit will be broken.

Referring. to the drawings, i

trates one form of apparatus for practicing the invention. Fig. 2 is a cross-section on line a, a. Fig. 3 is a modified form of the apparatus.

Referring to the views in detail, A repre- 3 5- sents a vessel of any proper material and size and form of construction.

B represents a diaphragm or separating member integral with .the walls of the main vessel or disconnectedly'arranged relatively 49 to the same, which diaphragm is pierced by an open passage-C.

D D, r'epresent circuit-terminal plates or electrodes supported by any suitable means in position relatively to the diaphragm prac- These plates are of sufiicient size to eflz'e'ct full electrical communication withthe fluid E contained in the receptacle A, which fluid is preferably acidulated water. Other terminals and other are fluids may be used; These terminals are conmooted to Figure 1 illus-' the wires F F, which for illustration form the primary-G of the inductiom coil H.

The action of the apparatus is as follows: Current passing through the fluid connecting the terminals so heats the part of the fluidconductor confined in the passage through the diaphragm as to cause such confined fluid to bev vaporized or become gaseous or to expand in the form of bubbles, which will interrupt the passage of the current, (or the most of the. current, if not all, )-whereu'pon thev gas or bubble willv tend to move from the confining-passage, and then the pressure of the fluid in the vessel will act to refill the passage,the current will be remade, another bubble 'formed,, and so on;

This operation will go on with high and manageable frequency of current interruption and with sustained regularity, so that (as is found after many and careful experiments) ahigh frequency and certain efficiency are secured for the purpose of interrupting an electric current of circuit. Such apparatus used to operate an induction-coil,'especially for the purpose of X-ray work, is found to effect greater steadiness as to the work 'of the secondary coil than that of any electric interrupter known to me. 7

Referring to Fig. 3, in lieu of the diaphragm of Fig. 1 I use a tube I, which is perforated at J or any other place as requirements may demand, which tube contains the terminal K, and another terminal K is contained in the.

outer vessel, the solution or fluid being the same as before. t V

In the last-mentioned case the tube constitutes a convenient member to be easily removed, so that tubes having passages of different sizes may be readily utilized to effect various rates of interruption. In the case of Fig. 1 the passage there shown maybe modified as to size, as of the small tube-er passage-closing tube L.,.

The frequency of interruption can be va ried in different ways. Thesize of the passage in the partition may be increased or sage may be of a fixed size and the terminals be brought closer together or placed farther apart than is shown. The electrical conductivity of the fluid can be varied and the gravby the removal therefrom between the terminals diminished. The pasity action of the fluid can be utilized for thesame purpose.

Generally speaking, it is found that after the apparatus has been in use for a short time the fluid in the containing vessel will be brought to a temperature that will remain practically stationary, whereupon the frequency of interruption becomes uniform, although it should be understood that the apparatus works instantly at ordinary temperature upon the closing of the circuit, though with an increasing rate of interruption as the fluid rises in temperature.

I am aware that electric-circuit interrupters involving electrolytic action have heretofore been suggested. In the present case the essential interrupting action is that of heating a confined part of a body of conducting fluid by the passage of the electric current through such part, so that it is formed into steam or gas.

That is claimed as new is 1. An electric interrupter comprising two electrodes, a conducting fluid between them, a perforated insulating separating medium between the electrodes forming areduced section of the fluid between the electrodes and means for subjecting said reduced portion of the fluid to pressure.

2. An electric interrupter comprising two @31 electrodes,a conducting liquid between them,

a perforated wall of insulating material between said electrodes, forming a reduced section of said conducting liquid, said reduced section of said liquid being subjected to thongs pressure of the superposed liquid.

3. An electric interrupter comprising tw electrodes, a conductingliquid between them, and a perforated insulating separating medium between the electrodes maintaining a uniform open relation of the liquid to the elec: trodes.

4. An electric interrupter comprising two circuit-terminals, a liquid conductor between them and in continuous open relation to them, a perforated wall of insulating material between them, and means for adjusting the size of the opening in the wall.

5. An electric interrupter comprising the vessel A, theouter electrode K, the tube land 59 contained electrode K, the said tube having an open passage J through the same, for the purposes set forth.

EUGENE w. CALDWELL.

Witnesses:

RoB'r. F. GAYLORD, JAMES M. CATLOW. 

